The Japanese airlock is only certified to do 12 airlock cycles per year. So for Bartolomeo to work efficiently, the NanoRacks Bishop airlock is required. Most CLPA payloads will be launched internally and brought outside with one of the airlocks. (It uses the same coupling interface as the Kaber deployer). Also the MISSE-X and MUSES payload facilities will require the airlock to exchange payloads.
The CEPF facilities will continue to be used when Bartolomeo is connected to the ISS.
Two European external payloads (CEPF); ACES (Atomic Clock Ensemble in Space) and ASIM (Atmosphere-Space Interactions Monitor), are still planned to launch. SOLAR has been on the ISS for much longer than initially planned.
Launch opportunities as external payloads are a scarce resource.
If I'm not mistaken, by 2018 all external FRAM and EPF locations will be occupied. JEM-EF also fills up fast so around 2020 there would be a requirement for Bartolomeo.
I prefer a contribution like this much more than a Orion service module, but we shall see what is decided at the European ministerial conference. The ESA memberstates have not even committed fully to ISS exploitation until 2020. For system development planning they need to look to live extension beyond 2024, the time Russia will stop supporting the ISS. But in Europe first the decision has to be made to support the program to 2020 and later 2024.
The ESA memberstates want to supply hardware and services to the ISS program. And I think Bartolomeo would be a nice hardware contribution to the ISS program along with data downloading service via EDRS. I think the EDRS communications terminal might be showed in some pictures.